Hydrogels comprise a network of polymer chains that are hydrophilic. The hydrogels may swell by the addition of a liquid. Hydrogels are cross-linked highly absorbent natural or synthetic polymers. Hydrogels may also possess a degree of flexibility very similar to natural tissue, due to their significant liquid holding capability. Common uses for hydrogels include drug delivery systems, contact lenses, medical implants, scaffolds in tissue engineering, sustained-release drug delivery systems, as absorbents in disposable diapers, EEG and ECG medical electrodes, water gel explosives, dressings for healing of burn or other hard-to-heal wounds, and reservoirs in topical drug delivery particularly topical drug delivery of ionic drugs delivered by iontophoresis, for example. Common polymeric precursors include, for example, polyvinyl alcohol, sodium polyacrylate, acrylate polymers and copolymers with a plurality of hydrophilic groups.
There exists a need for biocompatible, biodegradable hydrogels for medical applications such as wound healing and drug delivery.